Particle fragmentation is an important factor in the daily use of granular materials and in the powder and grain processing industries. In order to take into account particle fragmentation in discrete modelling, two approaches have been developed: 1) BCM for Bonded-Cell Method, in 2D and 3D (two projects with CEA Cadarache), which consists in representing a grain as a set of cells bonded together by a cohesive law, and 2) SCM for Split-Cell Method (with Los Andes in Bogota) where each grain can be replaced in several grains according to a rupture criterion depending on the stresses in the grains.

Our simulations show that the fragmentation process is intimately correlated to the force chains and depends on factors such as the initial particle shapes and sizes. During shear, a major effect of particle fragmentation is to attenuate or even cancel out packing dilatancy. In this case, the strain-stress curve no longer passes through a stress peak. Similarly, the residual state does not depend on the grain strength. Indeed, by fragmenting the polydispersity in size increases, and thus, geometrical compensations explain the independence of the resistance.

Main articles

5] D. Cantor, C. Ovalle and  E. Azéma, Microstructural origins of crushing strength for inherently anisotropic brittle materials , International Journal of Solids and Structures 238 (2022) 111399.
4] Rheology of granular materials composed of crushable particles, Eur. Phys. J. E (2018) 41: 50
3] Three-dimensional bonded-cell model for grain fragmentation, Comp. Part. Mech.
DOI 10.1007/s40571-016-0129-0
2] Split-Cell Method for grain fragmentation, Computers and Geotechnics 67 (2015) 150–156
1] Bonded-cell model for particle fracture, Phys. Rev. E 91, 022203 (2015)